1. Field of the Invention
The present invention relates to a technique for using communications to distribute picture data, and more particularly to a technique for providing picture data and control information of a camera device or other such input device for a live picture.
2. Related Background Art
(Live Picture Communications Systems)
There are distribution systems for distributing a captured live picture via the Internet, and providing instructions for settings, operations, etc. for a camera that serves as a picture capturing device.
In addition to providing picture distribution, these picture distribution systems and such can also provide camera controls such as pan, tilt, zoom, backlight corrections, etc. via a network.
Furthermore, the camera controls can also restrict areas to be captured. For example, a privileged user may be able to use all zoom functions provided to the camera, but a normal user may be limited to using only a portion of the zoom functions (e.g., the user may not be able to make complete use of a telescopic side). This may also apply with respect to the pan function and the tilt function.
(Third Generation Mobile Telephone Technology)
Third Generation (3G) mobile telephone technology service is now being provided. This mobile telephone service uses electromagnetic waves more efficiently, and has wide-bandwidth communication, than conventional mobile telephone service.
With Third Generation (3G) mobile telephone service, Internet accesses and other data communications are possible during telephone communication.
(MPEG-4 Codec)
Picture transmission and reception terminals have become more widespread. These range from personal information terminals (such as PDAs) and mobile telephone terminals which connect to mobile communication networks, to PCs which connect to broadband Internets. Due to the spread of these devices, in 1999, MPEG-4 was established by ISO as a moving picture compression encoding format. This format has high compression encoding efficiency covering a wide range of bit rates from several tens of Kpbs to several tens of Mbps, a strong resistance to transmission line errors in wireless and Internet-based communications, and other advantages.
(MPEG-4 Clip Techniques for Mobile Telephones)
Techniques have been offered for providing picture clips (picture files) to mobile telephone terminals.
In these services, the picture clip (picture file), which is encoded using MPEG-4 codec or the like, is downloaded from a server using a data communication function built into the mobile telephone terminal. After that, a decoder built into the same mobile telephone terminal is then used to display the picture on a screen of the mobile telephone terminal.
The data formats used for these picture clips conform to formats which have been adopted widely with the Internet, PC's, and the like. These include Microsoft's Advanced Streaming Format (ASF), ISO standard MP4 format (ISO/IEC 14496-1 Amd1 MPEG-4 system Version 2), and the like.
(Techniques for Associating Links and Commands with Picture Clips)
In formats such as Microsoft's Advanced Streaming Format (ASF) and Apple's QuickTime File Format, URL's and other hyperlink functions can be linked to the picture clip.
For example, the use of ASF makes it possible to define a “script command object”. Within this object, a list can be made with link information that is set to synchronize with the timeline to be followed when regenerating the ASF file. Furthermore, as the name “script command object” indicates, the use of ASF also makes it possible to author scripts and other command information, not just link information.
KDDI's ezmovie specifications also include a function for adding text telops (subtitles) with hyperlink functions to the picture clips. KDDI's Synchronous Telop Mark-up Language (STML) is used as a language for writing telops. This function enables the user to link audio communication, mail transmissions, home page links, etc. to the picture clip.